NICE DCV Resolution request bug

Question

I am currently using the NICE DCV Webclient SDK to embed the stream into a website. The layout of this website can change, so for that I want to change the resolution of the session with the `connection.requestResolution(width, height)` function. For some reason, however, the display layout (as returned by the displayLayoutCallback) then is sometimes slightly smaller than the requested resolution, for example:

```
resolutionRequest: 1106 | 824
Layout Callback: 1104 | 824
```

This then leads to a visible empty bar in the site-layout, as the view pixels are missing. The amount of pixels missing is inconsistent as well, ranging between 0-10 for width and height each.

The server is an Amazon Linux 2 Instance and the session is a simple virtual-session with GPU enabled. I am using the SDK version 1.2.1-358.

Where does this offset come from?

Thanks in advance!

Accepted Answer

HI,

that's the intended behaviour, not a bug.

Client can request any resolution using `requestDisplayLayout` or  `requestResolution` APIs. 
However, the request is not fulfilled by default. The DCV Server replies to the request with the closer available resolution (the one you see via the `displayLayoutCallback`). The resolution sent back from the server might depend on different factors like OS or if there are any blocked resolution on the remote system (e.g. in the X.conf file).

Answer

Thanks for your quick reply!

That makes sense. After some research I found that XServer limits resolutions to multiples of 8. Now at least I can research how to do a workaround or get a custom XServer resolution limit. 
Would it be possible to document the callback limitation in the official documentation?

NICE DCV Resolution request bug

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